Hey guys,
Recently the weather in Perth reached 42C - nothing out of the ordinary mind you, but my car overheated because of it...
Had the car looked at, and the water pump is leaking. No probs, easy fix.
BUT
Ever since then, the car has been playing up on acceleration, when you accelerate medium to hard, the car chugs - picture the tacho climbing normally 1k, 2k, 3k, 4k rpm...
But now it seems to climb more like this...1k, 2k, 1.5k, 3k, 2.5k, 4k, 3.5k etc...
The revs drop ever so slightly as you accelerate, and its very noticable and worrying.
I've had compression tests done, and checked the head, both in great condition.
My mechanic believes that the under bonnet heat when it overheated may have caused an electrical failure or sensor failure.
He wants the car for 3 weeks and $5,000 to run "tests".
I'm hoping this is a problem that SOMEONE has come across before, and can point me in the right direction?
Taking 3 steps forward and 1 step back.
-
TXCumtrensh
- Posts: 191
- Joined: Tue Jul 12, 2005 1:21 pm
- Car: None
-
Q45tech
- Moderator
- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (TXCumtrensh)
Aus$ vs US$ =0.7754 so he quoting $3877...................not sure of parts prices in Aus$ probably higher than US at retail.
Overheats and age usually result in knock sensor failures...........the sensor is sealed in plastic which cracks and the resistance changes along with sensitivity.
Bad KS don't illuminate the check engine light because it is not critical however acceleration suffers due to ecu going into fail safe regular fuel mode.
It was expected that the owner would notice something wrong and bring it in or mention it at it's every 90 day check up [oil change].
It is just standard proceedure to plug in the Consult everytime you visit a dealer because they are looking for failures to repair.
Replacing KS is so very very very common that we bet amongst ourselves when a new car comes in.
We have a standard list of problems with KS at top of list, then MAF and CAS connectors [which also don't show check engine light if they are intermitent [bucking and snorting ocassionally].
Removing the plenum opens up another can of worms because all the harnesses and hoses are brittle.
Always change both KS and its harness and EVERY hose [about 30 of them] so the process costs $1500 US...........but you will be good to go another 100,000 miles................plenum TB EGR clean up and new injector and plenum orings, fuel hoses, etc can add a few hours and say $500 US.
Change the spark plugs and reseal the valve covers [remove oil drips from spark plug well, etc] might as well be done at same time.....another $500 [at the same time].
So $2500/100000= 2.5 cents per mile
Overheats and age usually result in knock sensor failures...........the sensor is sealed in plastic which cracks and the resistance changes along with sensitivity.
Bad KS don't illuminate the check engine light because it is not critical however acceleration suffers due to ecu going into fail safe regular fuel mode.
It was expected that the owner would notice something wrong and bring it in or mention it at it's every 90 day check up [oil change].
It is just standard proceedure to plug in the Consult everytime you visit a dealer because they are looking for failures to repair.
Replacing KS is so very very very common that we bet amongst ourselves when a new car comes in.
We have a standard list of problems with KS at top of list, then MAF and CAS connectors [which also don't show check engine light if they are intermitent [bucking and snorting ocassionally].
Removing the plenum opens up another can of worms because all the harnesses and hoses are brittle.
Always change both KS and its harness and EVERY hose [about 30 of them] so the process costs $1500 US...........but you will be good to go another 100,000 miles................plenum TB EGR clean up and new injector and plenum orings, fuel hoses, etc can add a few hours and say $500 US.
Change the spark plugs and reseal the valve covers [remove oil drips from spark plug well, etc] might as well be done at same time.....another $500 [at the same time].
So $2500/100000= 2.5 cents per mile